1. Field of the Invention
The present invention relates to a process cartridge which includes cleaning means for removing toner used for image formation by an electrophotographic process, and to an image forming apparatus.
2. Related Background Art
Conventionally, an image forming apparatus using an electrophotographic image forming process adopts a process cartridge system. In the process cartridge system, an electrophotographic photosensitive member and process means acting on the electrophotographic photosensitive member are integrated into a cartridge which is provided detachably attachable to a main body of the electrophotographic image forming apparatus. According to this process cartridge system, a user of the image forming apparatus can perform maintenance of the apparatus independently without relying upon a serviceman. Thus, operability can be improved remarkably. Such a process cartridge system is widely used in the field of the electrophotographic image forming apparatus.
In addition, a single process cartridge is often selected for an image forming apparatus, in which case a large cleaning frame is used. Even in the case in which plural kinds of process cartridges can be selected, a cleaning frame is enlarged as an amount of toner is increased. The enlarged cleaning frame is also adopted even if the amount of toner is small.
However, when it is attempted to increase a capacity for containing toner, not only a toner frame of a large capacity process cartridge but also a cleaning frame has to be enlarged. In accordance with the increase in the size of the cleaning frame, the process cartridge is enlarged. Moreover, a size of an image forming apparatus main body is also increased in order to receive the enlarged process cartridge.
In addition, in the case in which a cartridge of a small capacity type with a small amount of toner is set for the enlarged cartridge, even if the cleaning frame still has room in its capacity for receiving the toner, the cleaning frame has to be replaced once the toner contained in the toner frame is fully consumed. Thus, for a user who performs a large quantity of image formation, the number of times of cartridge replacement increases. On the other hand, for a user who performs a small quantity of image formation, the large capacity process cartridge is expensive, and the user continues to use one process cartridge for a long period of time. Thus, image degradation or the like is liable to occur.